Cold Spring Harbor Laboratory Conference on Telomeres and Telomerase APRIL 30 ? MAY 4, 2019 Telomeres are specialized protein-nucleic acid complexes that protect the ends of eukaryotic chromosomes. In most eukaryotes, telomeres contain short DNA repeats that are maintained by the telomerase reverse transcriptase. Since telomerase counteracts the terminal sequence loss that accompanies replication of linear DNA, this enzyme is required for long-term cellular proliferation. The field of telomere biology grew rapidly once it was recognized that telomere dynamics and telomerase activation play a pivotal role in cellular senescence, human aging and tumorigenesis. A further impetus to the growth of this field has been the recognition of a rapidly increasing range of clinical syndromes resulting from short telomeres. These end-stage tissue failure phenotypes highlight the critical importance of telomeres in age-related disease in humans. As a result, the telomere field is now highly diverse and dynamic, representing a wide variety of research areas in which telomeres play crucial roles (aging, telomere syndromes, stem cells, cell cycle progression, cancer, meiosis and fertility, recombination, replication). The field encompasses research with mouse and human systems as well as insights gained from a wide variety of different model organisms (birds, frogs, flies, plants, nematodes, protozoa, budding yeast, fission yeast). The success of basic research in telomere biology was highlighted by the awarding of the 2009 Nobel Prize in Medicine/Physiology to Elizabeth Blackburn, Carol Greider, and Jack Szostak for their pioneering work in the discovery of telomerase, as well as the Breakthrough Prize in Life Sciences and the Gairdner award to Titia de Lange for her work on telomere protection. The previous ten Cold Spring Harbor Laboratory meetings on Telomeres and Telomerase have been crucial in bringing together a diverse group of researchers from all parts of the world, and have resulted in vigorous discussion and synergistic interactions stimulated by the presentation of mostly unpublished data. Because the CSHL Telomeres and Telomerase conference remains the only opportunity for scientists in this rapidly growing field to interact as a whole, this meeting is unique and of the utmost importance for the future of the field. Moreover, the format of CSHL meetings, for which nearly all talks are chosen from submitted abstracts, maximizes the opportunity for new independent investigators, postdocs and graduate students to present their work in a highly visible venue. These meetings have all had a uniformly high attendance rate from an international group of researchers, and the podium and posters have presented the major discoveries in the field well before publication.